In machines, such as reciprocating compressors, the health of the machine, i.e. the operating condition thereof, is largely determined by the condition of the valves and the piston rings.
In order to facilitate the analysis of the operating condition of a machine, it is an object of the invention to provide a method and apparatus by which tests for determining valve and piston ring condition can relatively easily be carried out. It is a further object of the invention to provide a machine which is adapted for carrying out such analysis without requiring the use of external equipment.